class A {
    int v1 = 10;
    int v2 = 10;
    public A() {
    }
    public void m1() {
        System.out.println("A m1");
    }
    public void m2() {
        System.out.println("A m2");
    }
}
class B extends A {
    int v2 = 20;
    int v3 = 20;
    public B() {
    }
    public void m2() {
        System.out.println("B m2");
    }
    public void m3() {
        System.out.println("B m3");
    }
}
public class Test {
    public static void main(String[] args) {
        A a = new b();
        a.m1();
        a.m2();

        System.out.println(a.v1);
        System.out.println(a.v2);
    }
}
